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  <title>Document</title>
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  <script>
    var largestPerimeter = function (A) {
      A.sort((a, b) => a - b);
      for (let i = A.length - 1; i >= 2; --i) {
        if (A[i - 2] + A[i - 1] > A[i]) {
          return A[i - 2] + A[i - 1] + A[i];
        }
      }
      return 0;
    };
    console.log(largestPerimeter([2, 1, 2]))

  </script>
</body>

</html>